The discovery of transient luminous events (e.g., jets, sprites, elves) has firmly established that the lower and upper atmospheres can be coupled impulsively through electromagnetic and plasma discharge processes related to thunderstorms and lightning. Active research work is currently being carried out to investigate the physics of transient luminous events and their effects on the middle/upper atmosphere. This talk will give an overview of the research work to study transient luminous events, including understanding their generation mechanisms and finding the evidence of the resulting modifications of the D region ionosphere. Furthermore, we will discuss how the research work in this field help advance the physics of lightning and plasma discharges in general.